The modern communications era has brought about a tremendous expansion of wireline and wireless networks. Computer networks, television networks, and telephony networks are experiencing an unprecedented technological expansion, fueled by consumer demand. Wireless and mobile networking technologies have addressed related consumer demands, while providing more flexibility and immediacy of information transfer and providing convenience to users.
Some mobile network providers allow multi-mode communication devices to access mobile network services, including for example, voice calls, data transfer, Internet Protocol Multimedia Subsystem/Session Initiation Protocol (IMS/SIP) and/or similar services, over a plurality of network interfaces. For example, a dual-mode communication device may access network services over both a cellular network connection through a base station (for example, connected using cellular access) and over a wireless local area network (WLAN) connection through a WLAN access point (for example, connected through WLAN access). This dual mode capability, which allows dual mode capable communication devices to access mobile network services over a WLAN is sometimes referred to as Unlicensed Mobile Access (UMA) technology and in Third Generation Partnership Project (3GPP) standards is referred to as Generic Access Network (GAN) standards.